With the advent of fiber lightguides for use in the communications industry, much emphasis has been placed on vapor disposition as a forming technique for a preform from which lightguides are drawn. In manufacturing preforms from which fiber lightguides may be drawn, vapors of materials such as SiCl.sub.4, GeCl.sub.4 and PoCl.sub.3 must be precisely delivered at controlled mass flow rates to a preform manufacture site where they are reacted and deposited on or in a support. This can be done by passing carrier gases such as oxygen, for example, through a supply of the material in liquid form to the deposition site as a mixture with the vapors entrained in the carrier gas.
In performing this operation, a vaporizer of the type known as a bubbler is ordinarily used. The bubbler generally has a carrier gas intake conduit that terminates with an outlet orifice located below the surface of a liquid material and an outlet conduit extending from the space above the surface of the liquid within the bubbler to the deposition site. Exemplary of deposition systems employing bubblers is that illustrated in U.S. Pat. No. 3,826,560.
Typically, the bubbler is supplied with a liquid that is caused to be transferred from a pressurized container which is made of glass and which is also used for shipping. Each of these containers is made with valved tubes which include a pressure application tube and a dip tube extending through and welded to a top of the container. The top of the container also includes a cleanout port to provide access to the interior of the container for cleaning and filling purposes.
The port in the top of the container could be eliminated and the container filled through one of the tubes which are later valved. However, the capability of cleaning the interior of the container of sediment deposits to permit its reuse instead of the costly alternative of discarding used containers requires the use of the port.
The construction of a container with a port requires that the port be sealed during shipment and during use. The seal must be such that it allows pressurization of the interior of the container during the transfer process. Furthermore, the seal must prevent leakage of the contents during shipment and must prevent the ingress of moisture which would contaminate the contents of the container.
One apparent solution is the construction of the container top to include a threaded port to be fitted with a threaded plug. This arrangement has not proved to be a feasible one since the plug tended to become welded to the material of the container so that the application of turning forces to the plug caused a rupture of the container.
The prior art is replete with patents dealing with closures. One such as that shown in U.S. Pat. No. 1,609,453, for example is a typical bottle closure comprising a cap and a carrier with the carrier being lifted to permit the cap to spring open. In recently issued U.S. Pat. No. 3,301,425, a sealing ring which is pressed around a skirt that surrounds a bulbous mouth of a container includes an upwardly directed sharp edge that protrudes into the skirt and prevents the ring from sliding along the skirt. The ring in the latter described arrangement is made of a material that will burst or be permanently deformed when the cap is removed from the bottle.
Seemingly the prior art is devoid of a reuseable closure for a container having a bulbous mouth which provides effective sealing of the container from egress of its contents or ingress of contaminants and which is easily removeable from the container to provide access to the interior.